Vacuum cleaner and method of operating same

ABSTRACT

A vacuum cleaner has a housing, a fan in the housing generating a suction air flow, an electric fan motor driving the fan, a dirt separator on the housing for separating dirt particles from the suction air flow, and a nozzle assembly. A suction pipe connects the housing to the nozzle assembly for drawing the suction air flow through the nozzle assembly. An external energy-storage unit on the suction pipe is connectable with the fan motor.

FIELD OF THE INVENTION

The present invention relates to a vacuum cleaner. More particularly this invention concerns a method of operating such a cleaner.

BACKGROUND OF THE INVENTION

A standard vacuum cleaner has a housing holding an internal motor-driven fan for generating suction air flow, a particle separator in the housing for stripping dirt particles from the suction air flow as well as a nozzle assembly and a suction pipe detachably connecting the housing and the nozzle assembly. In addition an external energy-storage unit is carried on the suction pipe.

Such a vacuum cleaner is known for example from GB 2,550,041 of applicant. The external energy-storage unit powers a motor of the nozzle assembly with electrical energy. However, the disadvantage of this arrangement is use as a conventional vacuum cleaner, because the mobility and flexibility of the vacuum cleaner are limited.

Furthermore, a market segment has increasingly established itself in recent times that prefers a battery-operated hand vacuum cleaner with a conventional suction pipe and a vacuum cleaner nozzle assembly. These so-called stick cleaners can be used can be used in a variety of ways for floor cleaning tasks. In particular, they can also be used with poor access to or a great distance from power outlets, for example on stairs. In order to ensure sufficient handiness such a unit must be made as light as possible, but this tends to limit the battery capacity for such a stick cleaner.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide an improved vacuum cleaner.

Another object is the provision of such an improved vacuum cleaner that overcomes the above-given disadvantages, in particular that has good cleaning performance and while being easy to handle.

SUMMARY OF THE INVENTION

A vacuum cleaner has according to the invention a housing, a fan in the housing generating a suction air flow, an electric fan motor driving the fan, a dirt separator on the housing for separating dirt particles from the suction air flow, and a nozzle assembly. A suction pipe connects the housing to the nozzle assembly for drawing the suction air flow through the nozzle assembly. According to the invention an external energy-storage unit on the suction pipe is connectable with the fan motor.

By putting the rechargeable battery unit forming the external power storage unit on the suction pipe, its weight is much less of a problem, in that its center of mass is relatively low and this weight is supported by on the floor via the nozzle assembly. The vacuum is particularly easy to use on floors, which is the main task such units are faced with.

Furthermore, the center of gravity of the external energy storage arrangement is close to the longitudinal axis of the suction pipe, which in the usual operating behavior also has a swivel axis for control of the nozzle assembly. The mass close to this pivot axis lead to a low moment of inertia, which also facilitates use.

Despite the identical weight of an energy-storage unit of the same size, mounting on the suction pipe leads to better operability than when in the housing. In the case of similar operating characteristics, a heavier energy storage with a larger capacity can be used. In addition, one can separate the housing also from the suction pipe and thus from the external energy-storage unit and use it in solo mode so that when the housing is very light.

A particularly light design of the housing can be achieved if it does not has its own energy-storage unit and the fan motor is powered exclusively by the external energy-storage unit. Such a configuration can lead to a particularly good concentration of the inert masses in the lower area of the suction pipe near the suction pipe. Such a configuration is an alternative to the solo operation of the housing and needs another energy supply, in particular in the form of a plug-in line-voltage connection.

In a further preferred embodiment of the vacuum cleaner the housing holds an additional, internal energy-storage unit to supply the fan. This enables a particularly flexible use both in the overall association of the vacuum cleaner as well as in the solo operation of the housing as a handheld vacuum cleaner without using the suction pipe and the attached nozzle assembly. The suction pipe is preferably detachably connected with the housing, with the external one energy-storage unit and/or with the suction pipe.

This allows one to use the vacuum cleaner variably in different configurations or even for storage or transport. By separating the housing, solo operation as a hand-held vacuum cleaner is possible. For cleaning hard-to-reach places furthermore, the suction pipe is separated and the housing can be used with part of the suction pipe. The nozzle assembly can also be connected directly to the housing.

Separation of the external energy-storage unit from the suction pipe manifold is made possible in addition to one short-term significant weight reduction as well as charging of the separated external energy-storage unit. A battery exchange for a fully charged alternative external energy-storage unit is possible.

To provide the electrical connection there are connection points between the suction pipe on the one hand and the external energy-storage unit, the nozzle assembly and the contact elements assigned to the housing are arranged in pairs. These make electrical contact with each other when the components are fitted together. The mechanical connection of the suction pipe and the suction pipe housing completes the electrical contact between the energy-storage unit and the fan motor.

In a preferred embodiment, the energy-storage unit has a measuring device displaying the charge level of the energy-storage unit. The measuring device is expediently connected with a controller in the housing controller. It is particularly preferred to display the charge level on the housing. The display can in particular be on the external energy-storage unit. When in the housing, the internal energy-storage unit can also be charged separately or as total value including the charge level of the external energy-storage unit.

The measuring device can in particular also be used as a so-called charge controller or as part of an energy management system. The measuring device then also serves to regulate energy consumption of the energy-storage unit in charging mode and/or when using the vacuum cleaner. This is particularly possible with a data line to the controller.

The connection of the measuring unit to the controller can in particular be via a separate data line. However, the data transfer can also be carried out via the power conductors, with the information transmitted as an alternating current component overlying the direct-current supply voltage. In this latter variant, an addition conductor is not necessary.

According to a preferred embodiment, the nozzle assembly carries a driven cleaning device. This can in particular be a rotatable cleaning roller, in particular a rotatably driven brush roller. The cleaning device is expediently electrically powered at least partly by the external energy-storage unit.

To operate the cleaning device, the external energy-storage unit or the nozzle assembly is provided with an external control device powered by the external energy-storage unit that supplies electrical energy to the motor of the cleaning device. The external controller can in particular include manual control elements, in particular a mechanical switch.

According to a further embodiment, the external controller can additionally or exclusively be operated by a controller in the housing. The connection between the external controller and the controller is preferably via a data line, in particular the same data line as the measuring unit or charge controller is connected with the suction pipe housing.

Also within the scope of the invention for the electrically driven cleaning device to directly powered via a supply line to the housing and supplied directly with electrical energy from there. The control and/or switching of the drive of the electrical cleaning device can then be done directly from the housing. This allows the control of the electrical cleaning device to be done together with control of the blower motor.

The invention also relates to a method of operating a vacuum cleaner. The vacuum cleaner comprises a housing holding a fan or blower for generating the suction air flow, as well as a dirt separator for separating entrained particles from the suction air flow. Furthermore, the arrangement comprises at least one nozzle assembly and one suction pipe connecting the housing with the nozzle assembly. There is an external energy-storage unit. According to the invention the fan is powered by the external energy-storage unit on the suction pipe. The mounting of the external energy-storage unit on the suction pipe facilitates handling the stick cleaner without limiting the capacity or size of the electrical energy-storage unit.

According to a first variant, the external energy-storage unit on the suction pipe provides the only energy source of the fan in the housing. For solo operation of the housing as a handheld vacuum cleaner there is a connection for an external energy source, in particular a cable with a line plug.

According to an alternative embodiment, the housing has an additional internal energy-storage unit for powering the fan. This is used for solo operation of the vacuum as a handheld vacuum cleaner if powering by the external energy-storage unit on the suction pipe is not possible.

The vacuum cleaner particularly preferably has a controller, in particular in the housing for operating the vacuum cleaner assembly. The energy-storage unit in the suction pipe and the energy-storage unit arranged in the housing can work in parallel and/or in series to power the fan.

For this purpose, the energy storage unit has its own electronic control system that controls charging and also powering of the fan.

It is particularly preferably provided that electrical energy of the storage unit carried on the suction pipe is primarily used to power the fan. Thus in normal operation, the internal storage unit is activated when the level of charge remaining in the external storage unit falls below a certain level. This preservers the charge if the internal storage unit to maintain the charge level of the internal energy-storage unit so that the housing can be used in solo operation as a hand vacuum cleaner.

As an alternative or in addition, in order to achieve a particularly high power, for example as a so-called boost mode, both energy-storage units can be used simultaneously for at least a limited period of time then deliver the maximum permitted power.

In a variant, there is at least one electrically driven cleaning device in the nozzle assembly. It is preferably also from powered by the external energy storage unit on the suction pipe. However, it is also possible that it is powered from the internal energy-storage unit and/or both energy-storage units if necessary.

The electrically driven cleaning device is particularly controlled or speed regulated by its own electronic controller. The motor control can in particular be mounted in the nozzle assembly or in or on the external energy-storage unit. The motor control is operated either via a control element connected to it, for example a button or switch, that is mounted on the housing of the vacuum cleaner or the external energy-storage unit. Alternatively or additionally, the controller can also be used by operated by the main controller in the housing. In particular, activation of the fan motor can be automatic at the same time as the electrical cleaning device. However, this can also be switched on or off separately.

According to a preferred embodiment, the external energy-storage unit also has a charge controller or an energy management system. This charge controller can be automatically converted into dependence on external operating parameters to be self-controlling or operated by external control signals, for example, from the control electronics within the housing.

In particular, the energy consumption or output of the external energy-storage unit can be regulated directly by the controller. This is the case in particular in the case of limited charging power, it can be provided that in charging operation first the internal energy-storage unit is charged. As soon as it is filled or after a predetermined charging time has elapsed, charging of the external energy-storage unit is initiated or increased. In particular, the charge controller and the controller can form a battery management system that prioritizes charging of the internal energy-storage unit and is also subordinates the external energy-storage unit to the existing charging current.

According to a particularly preferred embodiment of the invention, the internal energy-storage unit can be charged without connection to an external power source by electrical energy from the external energy-storage unit. This is particularly useful if the internal energy-storage unit is partially discharged in solo operation and then reconnected to the suction pipe and the vacuum cleaner. Such a transfer charge can in particular take place when the vacuum cleaner is switched off. If electrical parameters allow, this can also be done during operation. Despite the resulting conversion losses, the electrical range can be maximized in solo operation.

The electrical connection between the external energy-storage unit and the fan preferably takes place via a connection with at least two separate conductors. This is expediently at the joint between the suction pipe and the housing and is a plug or touch contact. Thus mechanical separation and connecting of the suction pipe and the housing takes place at the same time as electrical separation and connection automatically, provided the two components are fitted together.

The conductors preferably extend continuously into the suction pipe, where operation of lighting and/or an electrically powered cleaning device is possible.

To control the electronics of the external energy-storage unit and/or in the nozzle assembly and built-in electrical components, a data line can be provided. It can be designed as a separate further line. Alternatively, it is also possible to use the control signals as ac voltage components applied to the power rail with the standard dc power voltage. Communication between the individual components, in particular the charge controller, controller and motor control are preferably carried out via a bus system.

Alternatively, the structural components can also be designed to function independently of one another. This ability is particularly advantageous there is no a central control or control is not intended or does not work as intended. Also mixed operation of different components is possible that only uses some of the options of the control system.

For example, the charging electronics of the external energy store or of the internal energy-storage unit, when a certain limit voltage is exceeded, automatically switch to charging mode and, while drawing electrical energy, automatically conducts a charging process from the power rail.

The maximum voltage that is available from an energy-storage unit can also be made to depend on the state of charge of this energy-storage unit. If the charge controller determines that the voltage present on the conductors is higher than this voltage value, it separates the energy-storage unit from the conductors at least without a corresponding control input to prevent unintentional charging of the electrical storage cells. When the voltage value on the conductors due to the discharge of another energy-storage unit has fallen below this threshold value, the respective energy-storage unit switches on, so that now both electrical energy sources can be available. Such an automatic connection and disconnection makes possible operation that can do without a central control.

BRIEF DESCRIPTION OF THE DRAWING

The invention is described below with reference to figures showing embodiments. Therein:

FIG. 1A is a three-dimensional view of a vacuum cleaner according to the invention;

FIG. 1B is an exploded view of the vacuum cleaner from FIG. 1A; and

FIGS. 1A to 2C are schematic circuit diagrams of various vacuum cleaners according to several embodiments of the invention.

SPECIFIC DESCRIPTION OF THE INVENTION

FIG. 1A shows a vacuum cleaner 1 according to the invention with a housing 2. In the housing 2 there is a fan 3 for generating a suction air flow and that is driven by an electric fan motor 4 (FIGS. 2A-C). There is also a dirt separator 5 for stripping particles from the suction air flow. This dirt separator is a combination of a cyclone and a shaped fiber filter. Other techniques customary on the market are also applicable here.

The vacuum cleaner 1 further comprises a nozzle assembly 6 and a suction pipe 7 connected between the assembly 6 and the housing 2. The suction pipe 7 carries an external energy-storage unit 8.

The individual components of the vacuum cleaner 1 are detachably connected to one another. FIG. 1B shows these components in an exploded view separately from one another. In particular, the housing 2 can be separated from the other components of the vacuum cleaner 1 and used as a hand-held vacuum cleaner in solo operation. The arrangement of the vacuum cleaner assembly 1 as shown in FIG. 1A, constitutes a so-called stick vacuum serving as a full-function vacuum cleaner, for example capable of surface cleaning floors.

FIG. 2A shows a possible wiring of the vacuum cleaner 1 according to the invention. The suction pipe 7 is indicated schematically by a broken line, and the housing 2 by a dot-dash line. The suction pipe 7 carries the external energy-storage unit 8 that has several electrical storage cells 9 and a combined measuring unit and energy management system of a charge controller 10. The external energy-storage unit 8 is connected by conductors 11 with a controller 12 in the housing 2. The conductors 11 run from the external energy-storage unit 8 via the suction pipe 7 into the housing 2. Respective connectors 13 a and 13 b releasably connect the conductors between the housing 2 and the pipe 7, allowing them to be separated and reconnected. According to the invention the external energy-storage unit 8 can be connected to the fan motor 4. This is done in the embodiment shown via the conductors 11 and controller 12.

In this embodiment, the housing 2 also holds an internal energy-storage unit 14 with internal storage cells 15 and an internal charge controller 16. The drawing shows schematically that the internal energy-storage unit 14 has a smaller number of storage cells 15 or has a lower capacity and thus a lower weight and smaller dimensions than the unit 8. It is therefore significantly smaller and lighter than the unit 8.

The controller 12 in the housing operates the motor control according to s switch position of a slide selector switch 17 on the housing 2. A charge level indicator 18 is also provided on the housing 2 so the user can monitor the charge level of both the external energy-storage unit 8 and the internal energy-storage unit 14. For this purpose, the external charge controller 10 and the internal charge controller 16 report the current level of the battery cells 9 via a data line 19 back to the controller 12.

Furthermore, a connector 20 for external or even line power is provided on the housing 2. It is used to charge the external energy-storage unit 8 and the internal energy-storage unit 14 or for energy supply in solo operation. Alternatively, it is also conceivable that the connector 20 is used in solo mode if there is no internal energy-storage unit 14 or it is discharged.

Within the scope of the invention, it is also conceivable that the external energy-storage unit 8 is charged separately in a separate charging station. Particularly preferably, the external energy-storage unit 8 also has its own charge level indicator 21, which is either on during charging or when a push button 21 a has been actuated by the user to monitor the current charge level. For this purpose, a number of preferably multi-colored indicator lights 21 b may be provided.

Another preferred configuration of the interconnection is shown in FIG. 2B that corresponds essentially to FIG. 2A. In addition, the dashed line nozzle assembly 6 carries a cleaning roller 23 driven by a motor 22. This cleaning roller is preferably a brush roller mounted on the nozzle assembly 6 and is mechanically picks up dirt particles adhering to a floor surface. These are then combined with the suction air flow generated by the blower 3 and transported away. FIG. 2B shows that the cleaning motor 22 is operated by a motor control 24 in the nozzle assembly 6 and is connected by the data line 19 with the controller 12 in the housing 2. As a result, the selection switch 17 can turn the cleaning roller 23 on or off for a selected cleaning mode. In addition, a step switch 25 is provided on the suction pipe for control purposes. This allows separate activation or deactivation so that the vacuum cleaner can also be operated in suction mode without the brush roller or alternatively only with the cleaning roller without suction air flow. In FIG. 1A, the step switch 25 is on the top of the nozzle assembly 6. In contrast, a selector switch 26 is provided for mechanical switching of the vacuum cleaner floor 6 between use on a carpet and a smooth floor.

Another particularly simple variant of the interconnection is shown in FIG. 2C where control electronics are completely dispensed with. Both the internal energy-storage unit 14 and the external energy-storage unit 8 are without regulation with the common conductors 11 connected. Both the fan motor 4 and the roller motor 22 are each operated by a simple mechanical switch 27 a or 27 b that are interconnected electrically. This can be preferred for power selection with several switch positions that interpose different resistances into the circuit. 

What is claimed is:
 1. A vacuum cleaner comprising a housing; a fan in the housing generating a suction air flow; an electric fan motor driving the fan; a dirt separator on the housing for separating dirt particles from the suction air flow; a nozzle assembly; a suction pipe connecting the housing to the nozzle assembly for drawing the suction air flow through the nozzle assembly; and an external energy-storage unit on the suction pipe and connectable with the fan motor.
 2. The vacuum cleaner according to claim 1, further comprising: an internal energy-storage unit in the housing for powering the fan motor.
 3. The vacuum cleaner according to claim 1, wherein the suction pipe is detachably connected with the external energy-storage unit or with the housing.
 4. The vacuum cleaner according to claim 1, further comprising: a main controller in the housing for operating the fan motor and thereby regulating the suction air stream by controlling energy supplied to the fan motor.
 5. The vacuum cleaner according to claim 4, further comprising: a charge controller in the external energy-storage unit; and a data line connecting the charge controller to the main controller.
 6. The vacuum cleaner according to claim 1, further comprising: an electrically driven cleaning device on the nozzle assembly connectable or at least partially powered by the external energy-storage unit.
 7. A method for operating a vacuum cleaner according to claim 1, wherein the fan motor is at least partially powered by the external energy-storage unit.
 8. The method according to claim 7, wherein the external energy-storage unit has an external charge controller, an internal energy-storage unit and internal charge controller are provided in the housing, a main controller is provided in the housing and is connected to the external charge controller and to the internal charge controller for operating same.
 9. The method according to claim 8, wherein, in a first operating mode the external energy-storage unit is operated by the main controller to power the fan motor, and in a second operating mode the internal energy-storage unit is operated by the main controller to power the fan motor.
 10. The method according to claim 9, wherein in a boost mode the external energy-storage unit and the internal storage unit are both operated by the main controller to power the fan motor.
 11. The method according to claim 9, wherein in a transfer mode the external energy-storage unit is operated by the main controller to charge the internal energy-storage unit. 